Add `library_name` metadata

This PR adds the `library_name: transformers` tag to the model card's metadata. This enables the automated "How to use" widget on the Hugging Face Hub, making it easier for users to get started with the model using the `transformers` library.

README.md

@@ -1,15 +1,17 @@
 ---
-license: apache-2.0
+base_model:
+- facebook/opt-6.7B
 datasets:
 - databricks/databricks-dolly-15k
 language:
 - en
+license: apache-2.0
 metrics:
 - rouge
-base_model:
-- facebook/opt-6.7B
 pipeline_tag: text-generation
+library_name: transformers
 ---
+
 # init-OPT-6.7B
 
 [paper](https://arxiv.org/abs/2306.08543) | [code](https://github.com/microsoft/LMOps/tree/main/minillm)